Gas sensors are used in many commercial and industrial applications, including monitoring the environment for the presence of toxic or hazardous gases. It is frequently necessary to detect the concentration of a gas species at a level of a few parts per million. Since this gas species may be present at a low level, there is a need to remove or separate other extraneous gases or volatile organic compounds that would likewise be detected at the sensor and interfere with the detection of the gas species of interest.
In some sensors, high surface area carbon is used to adsorb extraneous volatile organic gas species. Other absorbents and chemicals may be utilized depending upon the species to be removed. Usually these absorbents and chemicals are supplied in a sealed glass tube, which must be broken so that the air sample can flow through. Such gas separation tubes are normally attached to the inlet of a gas sensor.
Usually, gas separation tubes are manually installed, one-at-a-time, onto a gas sensor. This is a time-consuming, and potentially dangerous process. First, a glass tube must be manually attached to the inlet of the gas sensor. Next, the ends or tips of the glass tube must be manually broken so that air can flow through the tube. Thereafter, the air sample is taken. Subsequently, the spent glass tube having broken glass tips must be manually removed from the gas sensor and disposed of. Afterwards, the glass shards from the broken glass tips must be collected and discarded. The art therefore continues to seek improvements in gas separation tube technology.
The current gas separation cartridge comprises multiple gas separation passages within one container, which passages are easily accessible by simply rotating the cartridge. A passage can be an individual tube or an individual chamber having an opening at both ends so that air can pass through on its way to the gas sensor. The passages are physically separated from each other by a gas impermeable, inert barrier.
There is only one installation of the cartridge, which permits access to multiple tubes, which is a time saver. Not only that, there is less interruption of air sampling. Similarly, there is just one removal of the cartridge. In addition, there is a decreased safety risk because there is no need to manually handle a tube having broken glass tips. Likewise, there is no need to clean up the broken glass shards. Here, the tube and glass shards remain contained within the cartridge. The cartridge is rotatable in order to access each individual passage. Thus, this current cartridge leads to improved operation and safety in gas sensor usage.